Hey, you: hands off the keyboard and step away from the computer!

Some developers really need to step away from their development job and study some things before getting back. And that's not to say worse things... I was navigating a Brazilian website today and suddenly I get a popup error that said (I've omitted some things and slightly changed some other things in order for this information not to be used by malicious people that might not have seen this error):

ERRO: /home/httpd/htdocs/[omitted].php (569) - mysql_connect() [<a href='function.mysql-connect'>function.mysql-connect</a>]: Access denied for user 'sistemabruboun'@'186.233.145.65' (using password: YES)
[BACKTRACE]
...
[FIM DO BACKTRACE]

Who in their right mind (or otherwise) would decide to add a username and password to a database in the error message???